There was no disagreement on relaxing this , but however we didn't find a way to version this yet.

For now we are allowing this as Clang feature (difference to a standard).

I assume it's not a separate feature and therefore not worth to start Clang extension for this. So I just modified the Clang manual for now. However, I could also start a new section in the extension document: https://clang.llvm.org/docs/LanguageExtensions.html